test: Fix panic in zip_with test

tests/main.rs

@@ -151,23 +151,10 @@ struct TestEffIO;
 
 define_test_type! { TestEffIO A }
 
-struct GluonTestable<F>(F);
-
-impl<F> tensile::Testable for GluonTestable<F>
-where
-    F: Future<Output = Result<(), Error>> + Send + 'static,
-{
-    type Error = Error;
-
-    fn test(self) -> tensile::TestFuture<Self::Error> {
-        tensile::Future(self.0).test()
-    }
-}
-
 fn make_tensile_test(name: String, test: TestFn) -> tensile::Test<Error> {
     let mut test = ::std::panic::AssertUnwindSafe(test);
     tensile::test(name, {
-        GluonTestable(::std::panic::AssertUnwindSafe(async move {
+        tensile::Future(::std::panic::AssertUnwindSafe(async move {
             let test = test.call_async(()).await?;
             let action = test.vm().get_global("std.test.run_io")?;
             let mut action: OwnedFunction<fn(OpaqueValue<RootedThread, TestEffIO>) -> IO<()>> =

vm/src/thread.rs

@@ -1260,15 +1260,15 @@ impl ThreadInternal for Thread {
                         );
                         e.call_state = ExternCallState::Poll
                     }
-                    _ => unreachable!("{:#?}", frame.state),
+                    _ => (),
                 }
             }
         }
         if context.stack.get_frames().len() == 1 {
             // Only the top level frame left means that the thread has finished
             return Err(Error::Dead).into();
         }
-        context = ready!(context.execute(cx))?.unwrap();
+        context = ready!(context.execute(cx))?.expect("Resume called on the top frame");
         Ok(context).into()
     }